I honestly do not think one of those charities sold your info. After all, THEY want your donations, they don't want you giving it away to others, not in todays economy.
I DO believe that even your cable company could have sold it.
BUT in all fairness, times are REALLY hard all over, and donations are really down while the list of those needing is really growing! It might just be somebody going through the phonebook, or you got on a telemarketer list and they just doing "computer generated dial-ups".
Go to the national DO NOT CALL registry and get your numbers on there.
THen if you get a call, do not say anything, but instead push the * button on your phone 3 times quickly and hang up.
That sends a "BAD LINE" signal to the computer that placed that call!
I donate to PBS and have NEVER had any soliciting calls after wards!